gpu, cmaa: reuse CopyTextureCHROMIUMResourceManager

gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 455 matching lines @@
     GLint y,
     GLsizei width,
     GLsizei height,
     GLsizei dest_width,
     GLsizei dest_height,
     GLsizei source_width,
     GLsizei source_height,
     bool flip_y,
     bool premultiply_alpha,
     bool unpremultiply_alpha) {
+  bool use_gl_copy_tex_sub_image_2d = true;
+#if defined(OS_CHROMEOS) && defined(ARCH_CPU_X86_FAMILY)
+  // glDrawArrays is faster than glCopyTexSubImage2D on IA Mesa driver,
+  // although opposite in Android.
+  // TODO(dshwang): After Mesa fixes this issue, remove this hack.
+  // https://bugs.freedesktop.org/show_bug.cgi?id=98478 crbug.com/535198
+  use_gl_copy_tex_sub_image_2d = false;
+#endif
   bool premultiply_alpha_change = premultiply_alpha ^ unpremultiply_alpha;
   // GL_INVALID_OPERATION is generated if the currently bound framebuffer's
   // format does not contain a superset of the components required by the base
   // format of internalformat.
   // https://www.khronos.org/opengles/sdk/docs/man/xhtml/glCopyTexImage2D.xml
   bool source_format_contain_superset_of_dest_format =
       (source_internal_format == dest_internal_format &&
        source_internal_format != GL_BGRA_EXT) ||
       (source_internal_format == GL_RGBA && dest_internal_format == GL_RGB);
   // GL_TEXTURE_RECTANGLE_ARB on FBO is supported by OpenGL, not GLES2,
   // so restrict this to GL_TEXTURE_2D.
-  if (source_target == GL_TEXTURE_2D && dest_target == GL_TEXTURE_2D &&
-      !flip_y && !premultiply_alpha_change &&
+  if (use_gl_copy_tex_sub_image_2d && source_target == GL_TEXTURE_2D &&
+      dest_target == GL_TEXTURE_2D && !flip_y && !premultiply_alpha_change &&
       source_format_contain_superset_of_dest_format) {
     DoCopyTexSubImage2D(decoder, source_target, source_id, dest_target, dest_id,
                         xoffset, yoffset, x, y, width, height, framebuffer_);
     return;
   }
 
   DoCopySubTextureWithTransform(
       decoder, source_target, source_id, source_internal_format, dest_target,
       dest_id, dest_internal_format, xoffset, yoffset, x, y, width, height,
       dest_width, dest_height, source_width, source_height, flip_y,
@@ skipping 264 matching lines @@
   decoder->RestoreTextureUnitBindings(0);
   decoder->RestoreActiveTexture();
   decoder->RestoreProgramBindings();
   decoder->RestoreBufferBindings();
   decoder->RestoreFramebufferBindings();
   decoder->RestoreGlobalState();
 }
 
 }  // namespace gles2
 }  // namespace gpu